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The Bioshale project, involving 13 partners throughout Europe, is co-funded by the European Commission under the FP6 program. The main objective of this project (which started in October 2004) is to identify and develop innovative biotechnological processes for ‘’eco-efficient’’ exploitation of metal-rich, black shale ores. Three extensive deposits have been selected for R&D actions. These are: (i) a site (in Talvivaara, Finland) that, at the outset of the project, had not been exploited; (ii) a deposit (in Lubin, Poland) that is currently being actively mined, and (iii) a third site (in Mansfeld, Germany) where the ore had been actively mined in the past, but which is no longer exploited. The black shale ores contain base (e.g. copper and nickel), precious (principally silver) and PGM metals, but also high contents of organic matter that potentially handicap metal recovery by conventional techniques. The main technical aspects of the work plan can be summarized as: (i) evaluation of the geological resources and selection of metal-bearing components; (ii) selection of biological consortia to be tested; (iii) assessment of bioprocessing routes, including hydrometallurgical processing; (iv) techno-economic evaluation of new processes from mining to metal recovery including social, and (v) assessing the environmental impacts of biotechnological compared to conventional processing of the ores. An overview of the main results obtained to date are presented, with special emphasis on the development of bioleaching technologies for metal recovery that can be applied to multielement concentrates and black shale ores.

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Shale, which occurs in the copper ore deposits belonging to KGHM Polska Miedź S.A., is the reason for a number of difficulties, at the stage of not only processing but also smelting. Gangue, in turn, getting in a feed during mining is a useless load of a concentrator and also contributes to lowering concentrating indexes. Its content in a feed is being evaluated at 15-30%. The multiple attempts to solve those issues by the methods of conventional mineral processing or even selective mining failed. In the range of work, research on the lithological composition and Cu content in 300 individual particles (selected from Rudna feed) have been carried out. Using those results, the simulation of gangue separation with an application of sorting have been done. The positive results have been received: introduction of a sorting operation causes, theoretically, removing of approximately 20-30% sorting feed mass as final tailings with Cu losses not bigger than 5-10%. It means that the capacity of Rudna concentrator can be increased proportionally. To confirm those results, industrial sorting trials are necessary, when appropriate sorters will become available. Additionally, one should take also into account that the finest classes of feed (-12.5 mm) could not be concentrated in a sorter. In the range of work, the preliminary tests of the industrial sorter (PRO Secondary Color NIR) for separation of the shale concentrate from Rudna concentrator feed have been carried out. The shale concentrates were received both from 12.5-20 mm class and +20 mm class. The concentrates produced from the coarse classes, for both technological sides had shale content at the level of 48-49%, with recovery of 52.9-60%. In the case of the finer class, shale content in the concentrates for both technological sides amounts to 30.9-35%, at the slightly lower recoveries than for coarse classes. Cu and Corg behavior in the sorting process were checked also, however, the results turned out to be not very interesting. Because the results of shale concentrate production by sorting have a significant potential for improvement, the further researches in this direction have been recommended, however, making them start off from elaboration of a technology for shale concentrate processing and calculation of a total balance of a concentrating process involving flotation and separation.